The answer is YES, and this type of shifter is a favorite among mountain bikers whose reliability needs and "field conditions" are already much more challenging than your average biker.

There are plenty of examples of situations where a wireless setup simplifies things.

I used to put wired speed/cadence sensors on my bike. Now I just zip tied two BLE gyros to the wheel and crank and things are vastly simpler. I've had them there for years and still haven't changed the battery. I've also never tangled the cables or had to fiddle with the mounts for a magnetic sensor.

It simplifies installation and getting a reliable, comfortable shifting setup, yes. Installation is simplified, especially in the case of internal and headset routing, which is something the target audience would deal with in case of cable-actuated derailleurs. Changes requiring adjustments over time due to the cable wearing out or stretching are eliminated, simplifying maintenance, both during and in between rides. On drivetrains with front and rear derailleurs, it has an optional adjustable algorithm that shifts both together for you and chooses the best gear combinations as you press up and down, simplifying operations. Auto-shifting is available on some models. There's more possibilities to put the shift buttons in the most ergonomic place, or even put them in more than one place, simplifying setting up your bike for comfort. That it doesn't simplify fixing your derailleur in the middle of a ride doesn't negate all of its benefits. Yes, the radio or battery could fail, but on the other hand it is less prone to go out of adjustment.

Also it has one killer feature and everyone that tries one also raves about how well it works. You know those little ramps stamped into the side of the sprockets on a cassette, that the chain moves up and down on as you change gears? Di2 delays your shift precisely until the start of a ramp, which makes shifting faster and works much better under load. That crunch and possible stuck chain when you shift to start a climb is basically eliminated.

Is it something a bikepacker will choose? Probably not. Is is something attractive to many other types of cyclists and simpler to install, use and maintain in ways they care about? Yes. I'm a weekend mountain bike rider, not at all competitive. I personally won't get one because of the cost but the features are quite attractive to me, while the risk and consequence of a dead battery seem low. There are many, many other things that are more likely to break during a ride, many of which will have you walking back. A dead Di2 battery means you are stuck in one gear, and if your chain has a master link or you carry a chain tool (target demographic definitely has one or both) you can change the gear in 2 minutes.

I thought of an analogy for HN. Think about water cooling in a gaming PC instead using the stock CPU cooler. It's more expensive, but generally higher performing and quieter and arguably looks cool. There's a certain demographic who thinks they are stupid because they must have extra parts so which are difficult to install and must be less reliable, and they may have one horrible failure mode of leaking liquid inside your PC. They might give the example of a mission critical server, and be right for this use case that it's not a good idea, at least at the scale of one machine. There's another demographic who don't think twice about buying them because the positives easily outweigh the negatives for them. This group can sometimes be seen telling the other group that they are out of date on it being difficult to install (you can even buy a case with it pre-installed) and reliability (modern all-in-ones almost never leak). They will most likely concede that for a mission critical server it's not the correct product.